Air pressure indicator



July 5, 1949. w. v. VARNER 9 5 AIR PRESSURE INDICATOR 2 Sheets-Sheet 1 Filed March 2, 1946 By @mwiu July 5, 1949 w, v, VARNER 2,4?5,533

AIR BRES'SURE INDICATOR 2 Sheets-Sheet 2 Filed March 2, 1946 I n ventor m W I, Z" W E tomeys Patented July 5, 1949 UNITED STATES PATENT OFFICE AIR PRESSURE INDIGATOK. William V. Varner, Atmore, Ala.

Application March 2, 1946,

2 Claims. 1

This invention relates to an air pressure indicator and-more particularly to a signaling device to indicate the-loss of pressure in a tire.

The primary object of the invention is to notify thedriver of a vehicle of the loss of pressure in a tire or tires without requiring the stopping of the vehicle and testing of each tire individually.

Another object is to indicate which tire on the vehicle requires additional inflation in order to restore the air pressure in the tire to a predeterniined value.

A further object of'the invention is to produce a visible warning signal together with an audible warning signal so that the driversattention will automatically be called to the signal when the pressure in any one of the tires falls below a predetermined value.

A further object is to regulate the pressure value at which the signal will be given.

The above and other objects may. be attained by employing this invention which includes a visual signal mounted on the instrument panel of avehicle for, each wheel, a pressure gauge carriedby each wheel, a fixed contact mounted adjacent the pressure gauge-and connected electrically to one of the signals, and a movable contact operated by the pressure gauge to engage the fixed contact and close an electrical circuit through its respective signal when the pressure in a tire on its respective wheel falls below a predetera mined value.v

Other features include means to regulate the pressure value at which the signal will be given.

Still other features include an audible signal operating in conjunction with the visible signals so as to call the drivers attention to the signal when the pressure in any one of the tires falls below a predetermined value.

In the drawings:

Figure 1 is a plan view of a chassis of a vehicle;

showing diagrammatically this, improved signaling system mounted thereon,

Figure 2 is a fragmentary face view of an instrument panel showing the visible and audible signals mounted thereon,

Figure 3 is a fragmentary enlarged. view of a wheel and tire equipped with my improved signaling system,

Figure 4 is a. transverse sectional view. taken substantially along the line 4-4 of Figure 3,

Figure 5 is an edge view of a wheel, certain portions being shown in section to illustrate the application of my invention thereto,

Figure 6 is a fragmentary sectional view taken substantially along the line lie-60f Figure 4, and

Serial No. 6513588 Figure 'l' is. a, fragmentary enlarged, sectional view taken substantially along the line 1-1 of Figure 4.

Referring to the drawingsin detail, a chassis designated generally H1: is equipped with the customary. axles H: onv which; the=wheels l2, |3, |4, ltand'the sparev L6 are mounted; Carried by the conventionalinstrument, panel H, of the vehicle is my, improved signal panel |'8., on. which is supported a series of: sockets for the reception of miniature electric signaling. lamps I9, 20, 2|, 22 and 23-, and a buzzer: or similar audible signal 24. Oneterminal of eachz of: the lamps I9, 20, 2|, 2? and 23. and one terminal; of. the buzzer 24 is connected throughavcommon conductor 25 to a power sourceifisuch asgtheordinary electric storage battery with which: the vehicle H1 is normally equipped. A, switch 2.1; is preferably arranged in the conductor 25 between the signal terminal and. the; power source 26 so that the signal may, be manually out out at the will of the user; This switch is preferably controlled by a button;28. which projects through the front face of the; panel as indicated in Figure 2. The terminalof-the signal l9 opposite that which is: connected to the conductor 25 has connected thereto a conductor 29 which leads to the left rear wheel |12= off the vehicleto be connected in a manner;tobehereinafter described toa pressure gaugeicarriedbythewheel. A similar conductor 30 leads from the terminal of the signal 20= opposite that connected with the conductor 2.5 to the pressuregauge: carried by the spare i6, and the terminal, of; the signal 2| opposite that connected to; the conductor 25 is connected to a conductor 3| which leads to the right rear wheel l3. A, conductor 32. isv connected to the terminal of the signal 22 opposite that which is connected to the conductor 25 and leads to the left front wheel l4 anda conductor 33 leads from the terminal! ofthe'signal- 23 opposite that connected; to the1conductor25 to the right front 7 wheel l5; The, terminal of the buzzer 24' opposite that connected to the conductor 25 is connected to 34,561'218S'Of conductors 34, 35, 3,6, 31 and 3,8 to the respective conductors 29, 3|], 3|, 32 and 33, so that when thecircuit is completed through any one of: the signals I9; 20', 2|, 22 or 23, the buzzer 24 will beset; into operation.

In order to regulate the flow of electrical power through the various signals, eachwheel l2, l3, l4, l5 and I6 is provided. with my. improved pressure gauge, designated generally 39. Each wheel comprisesthe conventional wheel body or disc Ml carrying at its periphery a conventional. rim 4| upon which is mounted in the conventional manquipped with a conventional inner ner a tire 42 e tube 43 which ventional tionary on the axle housi 40 is mounted on the hub row of spaced lugs 49 conventional hub cap 50.

Supported on an annular of insulating material exte brake drum 46 is an anti-fric peripheral band nding around the tion bearing 52, the o the cover 41 at or insulating strips 53, uter race of the antionductor 54 which is in espective conductor 29, e wheel on which the dean outwardly extending downwardly and around In a fixed contact against t 56 carried by the wheel ear. A suitable layer of separates the tongue 55 as will be readily underthe Figure 4. The yieldd on a suitable insulated ends through the wheel ding contact is connected f a conducting bolt 59 with h leads into the pressure se to be more fully hereinthe housing 6| is an air p through one end of which the cylinder. A bracket 65 e end of the cylinder throug 64 operates and is provide extending arm 66 in which a spring centering screw 61 is mounted. The'shank of the screw 61 aligns axially with the bore of the cylinder 63, and seated on the bracket surrounding the screw and bearing against the outer end of the plunger 64 is a compression coil spring 68 which normally tends to urge the plunger into the cylinder. A contact arm 69 is carried at the outer end of the plunger and is adapted to cooperate with a contact screw 10 which is adjustably mounted in an insulating bracket 1| carried by the cylinder 63 adjacent its open end. The conductor 69 is electrically connected with the screw 70 as will be readily understood upon reference to Figure 7. Communicating with the cylinder 63 near the end opposite that into which the plunger 64 extends, is a connecting nipple 12 to which one end of a flexible tube 13 is connected. The opposite end of the tube 73 leads to a T-shaped fitting 74 ressure cylinder 63 a plunger 64 enters Xtends from the open h Which the plunger (1 with an angularly stem 44 as illustrated necting the fitting 14 conventional air valve in Figure 4. Before conto the valve stem 44, the contained within the stem 44 is removed and placed in the fitting 14 to facilitate the inflation of the inner tube 43, and at the same time allow free access .of the air prescover disc 41 held stang 48. The wheel disc 45 by the usual annular which are enclosed in a sure contained i 13 and the cylin piston or plung outer surface conforming to ployed on air type.

In operation, it will be understood that the inner tube of the tire 42 is inflated in the ordinary manner and when so inflated, the pressure of air therein will register on the graduation 15 of the plunger 64, it being understood that the plunger will be forced out of the cylinder 63 against the compression of the spring 68. As the pressure in a tire decreases, the plunger 64 will be urged into the cylinder 63 under the influence of the spring 68 until the contact arm 69 engages the screw ill. This action will ground the conductor 60 and thereby establish a flow of electrical energy from the power source 26 through the respective conductor 29, 30, 3|, 32 or 33 and thus energize one of the signals I9, 26, 2|, 22 or 23. Simultaneously the buzzer 24 will be set into operation, thus giving an audible signal as well as a visual signal, the audible signal being given irrespective of which of the visible signals may be set into operation. It will thus be seen that as soon as any one of the tires of the vehicle, or even the spare, becomes soft and the pressure therein lowered beyond a predetermined point, its respective signal I9, 20, 2|, 22 and 23 will be operated so that the driver of the vehicle may easily and quickly determine which tire requires attention. Should it become necessary to demcunt the wheel from the hub, it is but a simple n the tube 43 to the flexible tube der 63 behind the piston 64. The er 64 is preferably provided on its with a plurality of graduations 15 the conventional graduations empressure gauges of the ordinary 45 may likewise be readily act in any way interfering with nt of the signaling system.

complished withou the reestablishme tatable element of t e indicator comprising a houstire, means establishing communication between the cylinder and the tire for conducting airinto the cylinder and exerting pressure on the plunger, yielding means resisting movement of the plunger under the influence of air entering the-cylinder, an adjustable contact carried by thecylinder, and. a cooperating contact carried by the plunger and adapted when the pressure within the tire falls below a predetermined value to engage the adjustable contact. W. V. VARNEB.

REFERENCES CITED The following referenkzes are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,115,022 Quick Oct. 2'1, 1914 1,144,834 Freeman June 29, 1915 5 1,924,921 Frank Aug. 29, 1933 2,063,452 McDonnell Dec. 8, 1936 2,248,047 Addy et a1 July 8, 1941 OTHER, REFERENCES Article on page, 410 of September 1928 edition of Science and Invention. 

